The BIOS follows what Asus has been using for sometime now. In order
to get the best results, we used the BIOS update software to upgrade
from the 141 version to the newest one, the 0504. The update is pretty straight
and works just fine. Probably the best we've seen, compared to the one of other
manufacturers.

The BIOS is separated in several tabs, each one holding several
sub-menus with different options. The first tab shows the date, SATA
drives and system information.

On the second tab named "AI Tweaker", users will find tons of
features. The motherboard includes an auto overclocking system, called
Ai Overclock Tuner with three different settings:

Manual

Auto

X.M.P

These options are easy to understand, even though only the last one
applies for DDR3 memory. If you have a pair of X.M.P enabled DDR3
memory, then you can use this option. It works like Nvidia's SLI
profiles...

Let's set now the Ai Overclock Tuner at Manual mode to be able to make some fine tunning:

The FSB can be set to up to 400MHz with the upcoming Intel processors. Most users will leave this option to Auto.

There are many memory dividers to play with, from 1:1 to 1:2.
The memory dividers are affected from the selected FSB, so in order to
have the highest possible options, leave the FSB to auto. We can see
that the BIOS reads the memory timings and displays them.

There are several modes for memory regulation either to enhance the performance or the stability

Many options also under the Ai Clock Skew:

While the voltage control has changed compared to previous models,
now the user can type the exact memory value and the BIOS will set it to
the closest one available. Asus P5E3 Deluxe WiFi can set it with 0.02V
interval that not many other manufacturers can:

For most of our tests we set DRAM at 1.90V. Notice that according to
the used voltage the colour changes from blue to yellow, purple and
eventually to red (max values):

Here is a list with all the available voltages and frequencies:

FSB from 200~800MHz with 1MHz step

Frequency bus PCI-E from 100~150MHz with 1MHz step

CPU Voltage: 1.10000V~1.70000V with 0.00625V interval

CPU PLL Voltage: 1.50V~2.78V with 0.02V interval

FSB Termination: 1.20V~2.48V with 0.02V interval

DRAM Voltage: 1.50V~2.78V with 0.02V interval

NB Voltage: 1.25V~2.53V with 0.02V interval

SB Voltage: 1.05V~1.23V with 0.15V interval

Under the Power tab, there are the usual temperature readings.

While at the Tools tab, we can find the Asus Express Gate feature that you can either enable or disable it: